This disclosure relates to multi-grid electron guns and systems with a single grid supply.
Multi-grid electron guns have multiple grids to control the flow of electrons. The multiple grids allow for particular beam shaping and relatively fast response time for beam current modulation and cutoff. In such multi-grid electron guns, the voltages applied to the grids may be different. Separate grid voltage sources are used to generate each of the different grid voltages. These voltages are generated outside of a high voltage enclosure of the electron gun and must be supplied to the grids through one or more high voltage cables and high voltage feedthroughs.
Multi-grid electron guns have a variety of applications. In one example, a multi-grid electron gun is used as part of an x-ray source for a computerized tomography (CT) scanner. In general, the grid voltage sources are mounted on a gantry of the CT scanner. However, the space on these gantries is limited. Each additional grid voltage source requires additional space on the gantry.